JALALABAD, Afghanistan - Taliban suicide bombers killed at least five policemen in Afghanistan's restive east on Tuesday, officials said, in a three-hour attack that coincided with a visit to the country by U.S. Secretary of State John Kerry.

The pre-dawn attack on a police compound in Jalalabad, eastern Afghanistan's largest city, came as the country braces for the beginning of the spring fighting season in the 11th year of the war.

One attacker detonated an explosive-laden car at the entrance of the Afghan National Police compound in a bid to let other attackers inside, provincial police chief Amin Sharif said.

"Three suicide bombers triggered their explosive vests and five were shot dead," he told Reuters, adding that five policemen were killed and four wounded.

During Secretary of State John Kerry's trip to Afghanistan, the country's leader Hamid Karzai backed off from his earlier statement that the U.S. was conspiring with the Taliban. NBC's Andrea Mitchell reports.

Amin said the attackers were armed with rocket-propelled grenades and light machineguns, sparking a three-hour battle with Afghan security forces. Six civilians were wounded.

Kerry was in Kabul to discuss transfer of security to the Afghan forces, as most U.S.-led NATO combat troops prepare to leave by the end of next year.

Rahmat Gul / AP

Afghan police and U.S. forces at the scene where eight suicide bombers attacked a police headquarters in Jalalabad on Tuesday.

Taliban spokesman Zabihullah Mujahid claimed responsibility for the attack in a text message.